Clinical news

By Bianca Nogrady
Infants who undergo less than one hour of general anaesthesia do not appear to suffer any adverse neurodevelopmental outcomes at age 5 years, an international study has found.

Writing in The Lancet, researchers reported the results of their randomised controlled trial in 722 infants undergoing inguinal hernia repair, who were randomised to either awake-regional anaesthesia or sevoflurane-based general anaesthesia.

At 5 years of age, the per-protocol analysis showed no significant difference between the two groups in full-scale intelligence quotient scores, which the authors said was ‘strong evidence of equivalence’.

There were also no significant differences in verbal, performance and processing speed composite scores, nor was there any difference in the proportion of children reported to have been diagnosed with a neurodevelopmental disorder.

‘We assessed the primary outcome at age 5 years because there is robust evidence for the emergence of the unitary construct of general intelligence and for the individual stability of that construct from middle childhood until adulthood,’ the researchers wrote.

The mean duration of general anaesthesia was 54 minutes, and no child was exposed to more than 120 minutes.

Coauthor and anaesthetist Professor Andrew Davidson, from the Royal Children’s Hospital, Melbourne, said the results were reassuring for children undergoing shorter durations of general anaesthesia.

‘About half the general anaesthesia that children get are about one hour or less, so the study is reassuring that for half of the anaesthetics that we give in children, there is no problem,’ said Professor Davidson, also Medical Director of the Melbourne Children’s Trials Centre at Murdoch Children’s Research Institute.

However, there is still the question of possible impacts from longer duration of exposure, which is being explored in a new study by Professor Davidson and colleagues.

He said studying longer anaesthetic exposure was challenging, because it was not possible to use spinal anaesthesia as a control for longer and more complex procedures.

‘We have to then compare two different general anaesthetics to see if there is a difference in neurodevelopmental outcomes,’ he told Medicine Today. There was also the further challenge of controlling for potential confounders in children who were likely to have other comorbidities related to their more complex surgery.Lancet 2019; 393: 664-677.